The use of inhalation devices in the administration of medicaments, for example in bronchodilation therapy is well known. Such devices generally comprise a body or housing within which a medicament carrier is located. Known inhalation devices include those in which the medicament carrier is a blister strip containing a number of discrete doses of powdered medicament. Such devices usually contain a mechanism of accessing these doses, usually comprising either piercing means or means to peel a lid sheet away from a base sheet. The powdered medicament can then be accessed and inhaled. Such a mechanism may also be used for dispensing medicament in tablet form wherein peeling away the lid sheet from the base sheet reveals a tablet for removal and subsequent consumption.
It is an object of the present invention to simplify the internal mechanism of a medicament dispenser for dispensing medicament in powder or solid form from a medicament carrier as described supra.
Yet another object of the present invention is to provide a device which is refillable by insertion of a replacement cassette containing a medicament carrier. The cassette may be replaced when the medicament carrier is empty. The device is therefore more ‘environmentally friendly’ as the majority of the device may be retained and is not disposable. It also allows the device to be fitted with additional features such as electronics which may not be cost effective on a completely disposable device.
It is a further object of the present invention that the cassette may be easily removed and that a new replacement cassette can be easily inserted. It is also desirable that the operation of the medicament dispenser be straightforward and non-complex and in particular that the number of separate steps involved in preparing the device for use be minimised. This is especially relevant where the device is designed for use in the delivery of medicament in emergency or rescue situations (e.g. asthma attacks) where simplicity and ease of use is paramount.
When not in use it is desirable from a hygiene standpoint that a mouthpiece, or other medicament exit channel, is provided with some kind of protective cover. The cover desirably acts both to prevent build-up of dirt and to prevent ingress of dirt into the body of the device through the mouthpiece or channel, which might then be subject to inhalation or consumption by a patient. It is also desirable that the cover is in some way attached or mounted to the device to minimise the risk that the cover is misplaced or lost. It is therefore a further object of the present invention for the body of the device to act as a mouthpiece or exit channel cover when the device is in storage and that the cassette is movable relative to the body to enable the mouthpiece or channel to be uncovered for use by the patient.
It is a further object of the invention to provide a medicament dispenser device suitable for use with a large number of discrete doses but which is of an acceptable size for use by patients.